USB Real-Time Clock (RTC) for Raspberry Pi

SBCSKU: 104147
Sale price £28.50
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Compatible with:

Awesome Extras

ANSMANNCR1220 3V Lithium Coin Cell Battery
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The Pi HutRaspberry Pi USB Extension & Shield Cable
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This is an open-source USB real-time clock for the Raspberry Pi, allowing your project to maintain accurate time and alarm/alert functions without internet connectivity - regardless of power cycles and reboots.

It uses a DS3231 RTC chip which runs the USB RTC with extremely high efficiency and accuracy. The RTC has cross-platform support which enables it to be used on different platforms such as Windows, MAC and more.

The USB connectivity is handled via an MCP2221 which is a USB-to-UART/I2C serial converter. The battery holder accepts a CR1220 battery.


  • Temperature-compensated crystal oscillator
  • DS3231 advanced processor
  • MCP2221 USB-to-UART I2C serial converter
  • I2C/SMBus supported clock and data lines
  • Supports full-speed USB (12 Mb/s)
  • 64-byte Transmit
  • 64-byte Receive
  • USB 2.0 Compliant
  • Low-Power Consumption



  • Battery Backup Input for continuous timekeeping
  • Operating temperature ranges: Commercial: 0°C to +70°C / Industrial: -40°C to +85°C
  • Low power consumption
  • Real-time clock counts seconds, minutes, hours, day, date, month and year (with leap year compensation valid up to 2100)
  • Two time-of-day alarms

Package Contents

  • 1 x USB RTC Module

Raspberry Pi & CR1220 battery not included

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